A Brooklyn mom of three was clinging to life yesterday after being struck in the head with a hammer by her boyfriend, police said.

Angela Hunt, a 34-year-old ex-model from East Flatbush, was upgraded from critical to stable at Brookdale Hospital after she was beaten at 11:30 p.m. Sunday, allegedly by the father of two of her three kids.

Hunt’s little boys, ages 2, 4 and 8, were at the family’s Linden Boulevard home during the assault, but it was not clear if they witnessed it.

Hunt was taken to the neurological intensive-care unit at the hospital where surgeons operated on her brain, said her mom, Karen Summers.

“My girl’s fighting,” Summers said.

Police are looking for Hunt’s 43-year-old boyfriend, who Summers said has shown a violent streak during the couple’s four-year relationship.

“He’s done this before. It got so bad he even threw a TV,” Summers said.

Summers said Hunt had a protection order against her boyfriend, but he would often find ways to manipulate his way into her apartment.

A neighbor saw the bloodied and stunned Hunt stagger out the building Sunday.

“I saw her sit down on the ledge, then walking back and forth” said Peter Campbell, 32.

“I heard her saying, ‘Why, why, why?’ ”

Campbell said Hunt’s 8-year-old boy came out to comfort his mom as neighbors called 911.

Hunt, who is also a painter, was called “a sweet, sweet woman” and a “good mother” by Summers.

The three boys were taken to live with a relative.

The vicious beating comes amid a spate of violent domestic-abuse cases in the city.

They include a Queens man who shot and killed his girlfriend outside her Brooklyn apartment over the weekend, then fatally shot himself in the head while fleeing the scene in his car.

A Long Island man, David Malone, is accused in the Sept. 13 stabbing death of his estranged wife. The couple had three young children.

There also was the infamous case this month involving Miguel Carrasquillo, who kidnapped his estranged wife, Nancy, at gunpoint from her job at Elmhurst Hospital in Queens. Cops eventually hunted him down in North Carolina.